Automatic control for air-brake systems



1km-i! 15 1924,

J. E. STIEGLMEYER AUTOMATIC CONTROL .FOR AIR BRAKEv SYSTEMS Filed Feb.e,

f attorney,

Fatented Apr. l5, 1924.

JOI-IN EDWARD STIEGELMYER, OF INDIANAPOLIS, INDIANA, ASSIG-NOR TO AUTO-MA'IIC CONTROL COMPANY, OF INDIANAPOLIS, INDIANA, A CORPORATION OF IN-DIANA.

AUTOMATIC CONTROL .FOR AIB-BRAKE SYSTEMS.

Application filed February To all whom t may concern.'

Be it known that I, Jol-IN EDWARD STinenL- Marian, a citizen of theUnited States, residinc' at Indianapolis, in the county of Marion andState of Indiana, have invented a new and useful Automatic Control forAir-Brake Systems, of which the following is a specification.

In my Patent No. 1,306,504, issued June 10, 191), I show an apparatuswhich was designed to be placed at the rear end of a train brake systemand was of such character that if, for any reason there was an improperreduction of train line pressure, such for instance as where thetrainmenhad rendered a portion of the system temporarily ineffective andhad failed to restore it to ell'ective condition, or where there weresuch leakagcs in the train line as .were not properly compensated by thepump, there would be an autonatic application of the brakes whollyindependent of the engineer so that the trainmen would be notified ofthe improper condition of the system and therefore investigate as to thecause.

In the use of the above mentioned apparatus, it was found that theremight be instances where the temporary ineffective portion of the systemwould be, say, only the caboose or one or two cars in front of thecaboose and, of course, under such circumstances the apparatus would bewholly ineffective to meet improper conditions which might exist in theforward portion of the train.

It is, therefore, the object of my present invention to introduce intoan ordinary train line brake system valve mechanisms, in large measuresuch as was disclosed in my above mentioned patent, one at the rear endof the system and the other in the forward end of the system, preferablybetween the engineers valve and the first set of brakes, this mechanismbeing so modified as to insure their co-operation with each other andwith the entire brake system in such manner that, in the ordinarymanipulation and control of the brakes through the engineers brakevalve, there will be no functioning of my devices but, whenever there isa train line pressure reduction for any cause, in any part of thesystem, below a fixed minimum determined by the adjustments of mydevices, there will be an automatic application of the s, 1922. sei-iaiNo. 534,363.

brakes, in the nature of an emergency application but at the reducedminimum pressure, which will be entirely automatic and independent ofthe engineer and the engincers valve, and equivalent, in that particularportion of the system in which the maximum train line pressure reductionhas taken place, to a light service application.

The accompanying drawings illustrate my invention: Fig. l is adiagrammatic illustration of an ordinary train brake system andincluding my improved devices; Fig. 2, an axial section of my valve online 2-2 of Fig. 3, and Fig. 3, a vertical section at right angles tothe plane of Fig. 2 and on line 33 of Fig. 2.

In the drawings, M indicates the main reservoir, P the pump, E theequalizing reservoir, e the engineers brake valve, 'I the triple valveon each car, A the auxiliary reservoir on each car, B the brake cylinderon each car and t the train line connecting the various parts which havebeen mentioned, n the usual manner. In the train line t, there are theusual angle cocks a0, one at each end of each ear.

Thus far the mechanism is standard.

Located at the front end of the system, preferably between thelocomotive and the tender, and at the extreme end of the system, are twoof my devices indicated generally by S and, in general, these devicesare the same as shown in my patent mentioned above, the constructionbeing as follows:

.Ar chamber 10 communicates through passage 11 with the train line. @neend of chamber 10 is enlarged te form a cylinder 12 in which piston'13is mounted. The stem 14 of piston 13 engages a sliding D-valve 15mounted in chamber 10 and co-operating with passages 16, 17 and 18. i

Communicating with cylinder 12 is a cylinder 19 which is of largerdiameter than the cylinder 12 and partially separated from cylinder 12by means of a ring 2O adapted to be engaged around its centralperforation by the leather face of piston 13, so that said piston mayserve to close communication between thc two cylinders 12 and 19.

Cylinder-19 is formed in a casing member 21 provided with an axial bore22 which receives inits outer end a plug 23 having an axial bore 241.Plug 23 is packed by a packing gland 25 and at the outer end of plug 23is the cap 26 which is screwed upon member 21 and forms a chamber 27 incommunication with bore 24. A passage 28 forms a comn'iunication betweenchamber 27 and passage 18. l

Mounted in cylinder 19 is a piston 30 which is adapted to be engaged bythe stem of piston 13. Leading from cylinder 19 between pistons 30 and13 is a groove 31 to atmosphere. Associated with piston 30 is a valve 32adapted to seat upon the inner end ot bore A compression spring 33 liesbetween piston 30 and valve 32, and said parts are shouldered at 34 insuch manner that it the spring 33 should break, valve 32 may act uponpiston 30 to drive it to its abnormal position. Spring 33 will becaused, by adjusting plug 23, to exert upon piston 30 a considerablepressure which, however, will be somewhat less per square inch than thepressure to which the train line pressure drops under ordinary brakeapplication through the engineers valve, say forty pounds per squareinch.y

Communicating with chamber 10 is a chamber 35 which communicates throughpassage 36 with chamber 37 which is in communication with atmosphere.Associated with passage 36 is a valve seat which is presented inwardlyinto chamber 35 and normally resting upon this valve seat is a checkvalve 38 normally held down by a spring 39. Formed below chamber 37 is acylinder 40 in which is mounted a piston 41 having a piston rod 42 whichis projected upwardly through the partition separating chamber 37 fromcylinder 40 and engages kthe lower end of the stem ot check valve 38.

Passage 17 leads into a cylinder 45 in which is mounted piston 46.Piston 46 engages a. D-valve 47 which co-operates with passages 48 and49. Valve 47 lies in a chamber 50 which is connected to supplementaryreservoir 105.

At this point. attention is called to the fact that instead otconnecting chamber 50 to the supplemental reservoir at the end of thechamber in the manner set forth in my above mentioned patent I connectthe end of the chamber with the trainV line through the pipe 100 andthen provide a pipe 101, leading from the side of chamber 50, whichconnects with the supplemental reservoir 10F. Ithen connect thesupplemental rreservoir with the train line by means of the pipe 103 andin this pipe I place a checlrvalve 104 which will permit flow from thesupplemental reservoir to the 'train line but will not permit flow fromthe train line to the supplemental reservoir.

A bleed passage 51 forms a bleeding connection between cylinder 45,through chamber 50, and the train line, when piston valve 47 is in itsnormal position, shown in Fig. 2.

Passage 48 communicates with the lower end of cylinder 40 and passage 49communi cates with atmosphere, these two passages being so arranged attheir point of entry into chamber 50 that the valve 47 may connect themor may uncover passage 48 to the supplemental reservoir through chamber50.

Chamber 50 is separated from the train line connection 10G by partition107 having an outwardly opening valve seat 108. Valve 47 carries a valvestem 109 which passes loosely through partition 107 and carries a valve110 which seats in seat 108 whenever valve 47 is shifted so as toconnect passage 48 with the chamber 50 and the supplemental reservoir.

ln the connection 111l` between chamber 10 and the train line, l place acheck valve 112 which permits flow from the train line to chamber 10 butwill prevent tlow from chamber 10 back to train line.

The operation is as follows: Upon establishment of train line pressure,the parts will assume the positions indicated in the drawings, trainline pressure entering chamber 10 and driving' piston 13 to the right,this piston coming into contact with ring 20 and closing communicationbetween cylinders 12 and 19. The movement ot piston 13 to thc rightdrives pistou 30 to the right against the pressure ci spring 33. Valve32 is normallyv seated so as to close the inner end oit bore 24. rllhisvalve is of smaller diameter than the piston 30, so the train linepressure, established in chamber 27 through passages 18 and 28 fromchamber 10, will not normally unseat it. rain line pressure also passesthrough passage 17 into cylinder 45 and drives piston 46 to the lett soas to shift the D-valve 47 to establish communication 'from the lowerend of cylinder 40, through passages 48 and 49, with the atmosphere.rTrain line pressure bleeds from cylinder through passage 51 and chamber50 to the supplemental reservoir and train line pressure also passesthrough pipe 106 past valve 110 through partition 10T into chamber 5uand from thence to the supplemental reservoir 105.

ln this connection one should not become confused by the fact that trainline pressure may enter chamber 45 'from both ends because the bleedingfrom train line to chamber through partition 107 docs not begin untilpiston 4G has been started toward the left by the entry oi" train linepressure into chamber 45 through passage 17 and there is sufficient timeinterval to permit piston 48 to be moved to the limit of its movementtoward the left before there is any equalization ot' pressures on theopposite sides of the piston.

Under normal application of the brakes through operation ot theengineers valve. the train line pressure in pipe 1.11 and chamber 10will .not be reduced below the strength of spring 33 and there will,therefore, be no operation of my device under ordinary conditions eitherat the rear end of the system or at the front end because it will benoted that train line pressure, having once entered chamber 10, istrapped in said chamber by the check valve 112 except as leakage mayoccur through the bleeding passage 51 and, under normal conditions, thisleakage is not sufficient to permit pressure reductions below thestrength of spring 33.

As a consequence it is apparent that the pressure on the right hand sideof piston 46 can not, so long as valve 15 fails to connect passage 17with passage 16, become reduced below the pressure on the left hand sideof piston 46 and consequently that there can be no accidental orimproper operation of piston 46 to any reduction in train line pressureunder service conditions through the engineers brake valve. For anymovement of piston 46 to the right, there must be a reduction ofpressure in chamber below the pressure of spring 33 and this reductionmust be due to a reduction in train line` pressure below the strength ofspring 33. Y i

If, however, for any reason, the train line pressure is reduced belowthe strength of spring 33, said spring immediately pushes piston to theleft and pushes piston 13 in the same direction. This movement willshift the valve 15 so as to disconnect passage 17 from chamber 10 andconnect it through passage 16 to atmosp-here, whereupon there is asudden reduction of pressure in cylinder and the pressure in thesupplemental reservoir serves to drive piston 46 to the right so as todisconnect passage 48 from atmosphere and connect it through chamber 50with the supplemental reservoir pressure; whereupon, the supplementalrcservoir pressure, passing through passage 48, in the lower end ofcylinder 40, shifts piston 41 upwardly so as to unseat check valve 38and thereby establishing communication between the train line andatmosphere through passage 11, chamber 10, passages 35 and 36 andchamber 37, thereby setting the brakes in all of that portion of thesystem which has an open train line controlled by my apparatus. That isto say, if one of the angle cocks ac has been closed my apparatus at therear end ofthe train or back of this angle cock will function asdescribed and the one at the head end will remain inactive because trainline pressure in front of the closed cock no is being maintained by thepump.

If, on the other hand, the pump is failing to function'for any cause, orif the engineer has allowed his valve to remain too long on lappedposiiton it will be apparent that there may be a drop in train linepressure Vbelow the strength of spring 33 and in that case my apparatuswill function as described.l If all of the angle cocks ac are open, thenboth of my devices will function as soon as the reduction in pressure intheir respective chambers 10 falls below the strength of spring 33, andif one of the angle cocks a@ is closed then my apparatus which lies infront of that cock will function if there is a pump failure or engineerslapped valve condition, and my rear device will function whenever theleakage from the system have been suflicient to bring the pressuresbelow the strength of spring 33 whether that has been due to a closedangle cock or failure of maintenance of train line pressure from anyother cause.

It will be apparent from what has been said that two of my devices,placed as indicated, will co-operate with the brake system as safetydevices to automatically set some or all of the brakes as a warning tothe engineer that the brake' system is not properly functioning and thiswarning will be givenwhenever and so long as the improper brake systemcondition exists.

Under some conditions, valve 15 may be moved to a position where itblanks passage 17 and there may b-e suf'cient leakages past valve 47that?y the pressures in chambers 45 and 50 and the supplementalreservoir might be exhausted and there would then be a failure of piston46 to function.

This, of course, would cause the whole apparatus to fail to function. Itis for thatv reason that I have provided the connection between chamber50 and the train line controlled by valve 110, this connection perimitting a. maintenance of pressures in chambers 50 and 45, under normalconditions, which will insure at all times a sufficient pressure inchamber 50 to cause movement of piston 46 to the right whenever thepressures in chamber 45 are reduced through passage 17 by the propermovement of valve 15.

I claim as my invention:

1. The combination with-an air brake sys-- tem comprising means formaintaining train line pressure, a plurality of braking devices andassociated control valves, and an engineers valve, of two control valvemechanisms, one located between the engineers valve and the braking unitand the other at the end of the braking unit, each of said control valvemechanism comprising a normally closed valve controllingcommunicationbetween the train line and atmosphere, a manipulatingmember for said valve normally held in inactive rposition by train linepressure, a spring for driving said manipulat ing member to activeposition upon reduction of train line pressure below a desired minimum,and connections for trapping train line pressure against saidmanipulating member so as not to be subjected to noriii) Cil

mal variations in train line pressure due to service manipulation of theengineers valve.

2. The combination with an air brake system comprising means formaintaining train line pressure, a plurality of braking devices andassociated control valves, and an engineers valve, ot a control valvemechanism connected to said system and comprising a normally closedValve controlling communication between the train line and atmosphere, amanipulating member for said valve, normally held in inactive positionby train line pressure, a spring for driving said manipulating member toactive position upon reduction ot train line pressurebelow the desiredminimum, and connections for trapping train line pressure against saidmanipulatingmember so'as not to be subjected to normal variations intrain line pressure due to service manipulation of an engineer-s valve.

3. An air brake applying safety valve, comprising a connection for trainline, an exhaust port communicating with said train line connection, acheck valve normally closing said exhaust port, pressure controlledmeans 'for liftingsaid check valve from its seat, train line pressurecontrol means for controlling the application of opening Yforce to thecheck valve, a check valve arranged in the connection between said trainline pressure controlled means and the train line for limiting flow insaid connection to said pressure controlled means from the train line, aspring acting upon said train line -pressure controlled means in thedirection kmental reservoir and train line. a check valve in saidconnection permitting flow only from the supplemental reservoir to thetrain line, a cylinder having a bleed passage connection with saidsecondary valve chamber, a piston mounted in said cylinder, a secondaryvalve mounted in the secondary valve chamber and connected with saidlast mentioned piston, a passage controlled by the primary valve forconnecting the primary Valve chamber with the secondary cylinder, acheck valve controlling outflow to atmosphere, a piston for acting uponthe last mentioned check valve in opening direction,

a cylinder containing said piston, a passage connecting said lastmentioned cylinder and the secondary valve chamber in a position to becontrolled by the secondary valve, a piston acting upon the primarypiston in the direction opposite to train line pressure, a passageconnecting with the primary valve chamber, a cylinderl containing thelast mentioned piston and communicating with said last mentionedpassage, a valve closing said communication, a spring arranged betweensaid last mentioned piston and valve to normally hold said valve closedand to act upon the piston in the direction opposite to the direction oftrain line pressure upon the primary pistou, a direct connection betweenthe secondary valve chamber and train line, and a valve controlled bythe piston in the secondary valve chamber for closing communicationbetween said secondary valve chamber and the direct connection withtrain line when the secondary valve is shifted to open connmmicationbetween the secondary valve chamber and the cylinder of the piston whichcontrols the check valve leading to atmosphere.

5. The combination with an air brake sys` tem comprising means formaintaining train line pressure, a` plurality otl braking devices andassociated control valves and an engineers Valve, of a control valvei'nechanism connected to said system and comprising a normally closedvalve controllingcommunication between the train line and atmosphere, amanipulating member for said Valve normally held in inactive position bytrain line pressure, a spring for driving said Ymanipulating member toactive position upon reduction of train line pressure below the desiredminimum, and means for delaying the action of said manipulating member.

6. The combination with an air brake system comprising means 'formaintaining train line pressure, a plurality of braking devices andassociated control valves and an enginecrs valve, of a control valvemechanism connected to said system and comprising a normally closedyalve controlling communication aetween the train line and atmosphere, amanipulating member tor said valve normally held in inactive position bytrain line pressure, a spring for driving said manipulating member toactive position upon reduction oi' t `ain line pressure below thedesired minimum, and means tor rendering said spring ineiiective whiletrain line pressure is reduced by normal manipulation of the engineei"svalve.

7 The combination with an air brake system comprising means formaintaining train line pressure, a plurality of braking devices andassociated control valves and an engineers valve, of a controlyalvemechanism connected to said system and comprising a normally closedvalve controlling communication between the train line and atmosphere,pressure operated means for operating said valve, a normally closedvalve for controlling the admission of pressure to said pressureoperated means, a pressure balanced piston `for operating said valve, anormally closed valve controlling the pressure balance on said piston, aspring tending to open said valve, train line pressure o erated meansfor rendering said spring ine ective whereby the spring will becomeetfective upon the reduction ot the train line pressure below a desiredminimum, and means for preventing the reduction of train line pressureon said train line pressure operated means by the normal manipulation ofthe engineers valve.

8. rlhe combination with an air brake system comprising means formaintaining train line pressure, a plurality of braking devices andassociated control valves and an engineers valve, of a control valvemechanism connected to said system and comprising a normally closedvalve controlling communication between the train line and atmosphere,pressure operated means for operating said valve, a valve forcontrolling the admission of pressure to said pressure operated means, abalanced piston subjected to train line pressure on both sides oroperat-ing said valve, a second valve controlling the admission of trainline pressure to one side of said piston which when opened permits areduction of pressure on one side of said piston to cause the same toopen its valve, a spring tending to open said second-mentioned valve,means subjected to train line pressure for balancing the eliectof saidspring and maintaining said secondmentioned valve closed whereby whentrain line pressure drops below a predetermined minimum saidsecond-mentioned valve will be opened to cause the operation of saidpressure operated piston, and means for shutting od train line pressureon the opening side of said piston after the piston has operated itsvalve. Y

9. The combination with an air brake system comprising means formaintaining train line pressure, a plurality of braking devices andassociated control valves and an engineers valve, of a control valvemechanism connected to said system and comprising a normally closedvalve controlling communication between the train line and atmosphere,pressure operated means for operating said valve, a valve forcontrolling the admission o pressure to said pressure operated means, abalanced piston subjected on opposite sides to train line pressure foroperating said valve, a second valve controlling the admission of trainline pressure to one side of said piston, a spring tending to open saidvalve, means subjected to train .line pressure for rendering said springineffective whereby when the train line pressure falls below apredetermined minimum said spring will operate said second-mentionedvalve to reduce the pressure on one side of the piston to permit thepiston to operate its valve, and means for insuring suiiicient pressurefor operating said pressure operated means for a short period in eventthe train line pressure is too low to operate the same.

10. The combination with an air brake system comprising means formaintaining train line pressure, a plurality of braking devices andassociated control valves and an engineers valve, of a control valvemechanism connected to said system and comprising a normally closedvalve controlling communication between the train line and atmosphere,pressure operated means for operating said valve, means for supplyingtrain line pressure to said operating means, means controlling theadmission of said train line pressure to said operating means,manipulating means for said means normally held in inactive position bytrain line pressure, a spring for Aoperating said manipulating means toactive position upon reduction of train line pressure below the desiredminimum, and means for automatically shutting off pressure to saidpressure operated means after a predetermined period.v

1l. The combination with an air brake system comprising means formaintaining train line pressure, a plurality of braking devices andassociated control valves and an engineers valve, of a control valvemechanism connected to said system and comprising a normally closedvalve controlling communication between the train line and atmosphere,pressure operated means for said valve, means for supplying train linepressure to said p-ressure operated means for operating said valve, asupplementary pressure supply -i'or said pressure operated means,manipulating means for controlling the admission of pressure to saidpressure operated means normally held in inactive position by train linepressure, a spring device for driving said manipulating means to activeposition upon reduction of train line pressure below the desiredminimum, and means for preventing the admission of pressure to saidpressure operating means longer than a predetermined period.

In witness whereof, l have hereunto set my hand at indianapolis,llndiana, this Aith day of February, A. D. one thousand nine hundred andtwenty two.

JOHN EDWARD STIEGELMEYER.

